This invention relates to modular computer peripherals and more particularly to a modular peripheral combining a pager with a PCMCIA based fax-modem.
Today's working professional relies heavily on modern technology; computers, telephones, modems and facsimile machines have become indispensable office equipment. The mobile professional supplements office-bound equipment with laptop computers, cellular telephones, pagers, and fax/modems to maintain the same degree of connectivity while away from the office. In an effort to capitalize on the mobile professional's need for an "office-in-a-briefcase", devices which combine the functionality of a pager, a facsimile machine, and a computer modem into a single computer peripheral have been developed. Such a device, combining a fax/modem and a radio pager into a single PCMCIA peripheral is disclosed in co-pending commonly assigned U.S. patent application Ser. No. 08/174,797, filed Dec. 29, 1993, which is incorporated herein by reference in its entirety.
While a combination device has many benefits, there are instances when a professional does not need, or want, to carry all of the aforementioned devices. For example, while attending a business lunch, the professional may desire to carry only a pager, without bringing a laptop computer. Using previously known devices, it is possible to remove the combined pager/fax/modem devices from the laptop and thus have a pager without the laptop. However, due to the specified dimensions of a PCMCIA slot and card, and due to the need to provide the pager with a battery for power when it is not connected to the computer, the combined pager/modem device has bulkier packaging than either the pager or PCMCIA modem alone. In addition, the relatively fragile transition between the thin PCMCIA card portion of the device and the bulkier pager portion of the device is vulnerable to bending stresses. It would therefore be advantageous to be able to separate the pager component of the combined pager/fax/modem peripheral from the remaining components. In this way, the pager may be carried separately or coupled to the remainder of the combination peripheral and installed in a laptop computer, as the user desires.
In order to separate the pager from the remainder of the pager/fax/modem device, circuitry must be provided so that the computer can selectively communicate with either the fax/modem or the pager. Furthermore, the fax/modem portion must be capable of operation regardless of whether the pager is attached or not. Co-pending commonly assigned U.S. patent application Ser. No. 08/313,414, for PCMCIA SERIAL INTERFACE, filed Sep. 27, 1994 and which is incorporated herein by reference in its entirety, discloses circuitry for providing such an interface between a detachable pager and a PCMCIA based fax/modem card.
When the pager portion is attached to the fax/modem portion of the peripheral, the pager draws power from the laptop computer via the fax/modem PCMCIA card. Since the pager draws power from the laptop, it is not necessary to provide a separate power source (e.g. a battery) for the pager when it is coupled to the fax/modem. Indeed, since the power source for the pager contributes a significant fraction of the total weight of the pager, removing the battery from the pager when it is coupled to the fax/modem reduces the weight of the pager and therefore reduces the stress placed upon the mechanical and electrical joint between the pager portion and the fax/modem portion of the peripheral.